Abstract:

A method of electromagnetic interference assessment applicable to a
receiver, comprising the following steps: initially, scanning a plurality
of frequencies; next, for each scanned frequency, measuring corresponding
signal strength value; finally, based on the correspondence between the
frequencies and the signal strength values, acquiring an analysis curve
graph, furthermore assessing the extent of electromagnetic interference
occurring in the receiver through the acquired analysis curve graph.

Claims:

1. A method of electromagnetic interference assessment, characterized in
that it is applicable under a condition in which a receiver is not
connected to an antenna to receive at least one digital radio frequency
signal, the assessment method comprises the following steps:scanning a
plurality of frequencies;measuring corresponding signal strength value
for each of the frequencies;assessing the extent of electromagnetic
interference of the receiver based on the measured signal strength
values.

2. The method of electromagnetic interference assessment according to
claim 1, characterized in that, before the step of scanning the
frequencies, it further comprises the following steps:providing an
electromagnetic interference assessment procedure in the receiver;
andexecuting the electromagnetic interference assessment procedure to
assess the extent of electromagnetic interference of the receiver at each
frequency.

3. The method of electromagnetic interference assessment according to
claim 1, characterized in that, in the step of scanning the frequencies,
it comprises the following steps:setting a frequency reception range;
andsequentially scanning from the lowest frequency in the frequency
reception range to the highest frequency therein.

4. The method of electromagnetic interference assessment according to
claim 3, characterized in that, in the step of measuring the signal
strength values, the signal strength value of a frequency is measured
each time the frequency is scanned, until all corresponding signal
strength values of the frequencies in the frequency reception range are
measured.

5. The method of electromagnetic interference assessment according to
claim 4, characterized in that, in the step of assessing the extent of
electromagnetic interference based on the signal strength values, it
comprises the following steps:recording the signal strength values;
andacquiring an analysis curve graph based on the correspondence between
the frequencies and the signal strength values.

6. The method of electromagnetic interference assessment according to
claim 5, characterized in that, in the step of assessing the extent of
electromagnetic interference based on the signal strength values, it
further comprises the following steps:the closer the signal strength
value approaches to zero, the smaller the extent of electromagnetic
interference at the corresponding frequency of the signal strength value
is; andotherwise, the greater the extent of electromagnetic interference
at the corresponding frequency of the signal strength value is.

7. The method of electromagnetic interference assessment according to
claim 5, characterized in that, in the step of assessing the extent of
electromagnetic interference based on the signal strength values, it
further consists of the following steps:providing at least one preferred
curve graph;comparing the analysis curve graph with the preferred curve
graph; anddetermining whether or not electromagnetic interference of the
receiver occurs based on the comparison result.

8. The method of electromagnetic interference assessment according to
claim 7, characterized in that it further consists of the following
steps:displaying the signal strength values; anddisplaying the analysis
curve graph.

9. The method of electromagnetic interference assessment according to
claim 1, characterized in that the receiver is a Set Top Box (STB).

10. The method of electromagnetic interference assessment according to
claim 1, characterized in that it uses an automatic gain control to
detect the corresponding signal strength value of each frequency.

11. The method of electromagnetic interference assessment according to
claim 3, characterized in that the frequencies are respectively measured
for the corresponding signal strength value thereof is of step-wise
increment.

Description:

BACKGROUND OF THE INVENTION

[0001]1. Field of the Invention

[0002]The present invention relates to an assessment method; in
particular, to a method of electromagnetic interference assessment.

[0003]2. Description of Related Art

[0004]Thanks to rapid and striding advancements in modern communication
technologies and compression technologies, television broadcast around
the world has now gradually evolved from analog television broadcast into
digital television broadcast. The revolution of digital broadcast led to
dramatic development of relevant industries, in which digital TV sets and
Set Top Box (STB) are just a few of the examples.

[0005]Present digital media services are mostly provided by program
producers or telecast companies that broadcast digital radio frequency
(RF) signals from the transmitter antenna, and users may employ a digital
TV set, a STB, or other digital reception system supporting the utilized
broadcast standards to receive the digital RF signals for various further
digital processes, then rendering the transmitted TV programs or
audio/video (AV) multimedia information. Because of the aforementioned
devices all use built-in receivers to receive signals, thus the
performance in the receiver directly influence the quality of received
signals.

[0006]In addition to possible distortion or interruption in the digital RF
signals because of multi-path interference during transmission, poor
design in the printed circuit board of the receiver may further result in
reduced reception performance as well. Based on the pursuit of compact
size, the components and layouts configured on the printed circuit board
are becoming denser than ever; in case of inappropriate layout design,
the printed circuit board may radiate undesirable electromagnetic
interferences, thus causing signal deterioration problem at a specific
frequency. Additionally, length and width of wires may also influence the
resistance and inductance thereof, accordingly generating complicated
electromagnetic effect that causes impact on frequency responses.
Therefore, in order to receive the correct channel, the reception system
of the receiver needs to perform tuning processes to verify if there is
any possibility that electromagnetic interference may occur in later use.

[0007]However, commonly used methods at present days for said tuning
processes need to perform electromagnetic radiation tests on the receiver
in the electromagnetic conformity laboratory to locate the frequencies
vulnerable to electromagnetic interference, and based on engineer's
experience and knowledge to modify the configuration, and then repeatedly
execute the electromagnetic interference tests until the reception
function is qualified for specification. The aforementioned operations
may consume a significant amount of time and expenses, and the
complicated procedure in the strict tuning processes may limit the
development of receiver as well.

SUMMARY OF THE INVENTION

[0008]Regarding the issues which described heretofore, the present
invention provides a method of electromagnetic interference assessment,
which, under the circumstances of a receiver not being connected to a
reception antenna, records the signal strength values of multiple
frequencies in the entire frequency reception range, and assesses which
frequencies are influenced by electromagnetic interference based on the
acquired signal strength values, so as to effectively observe the extent
of influence caused by electromagnetic interference, furthermore enabling
configuration modification to eliminate radiation sources.

[0009]Therefore, the objective of the present invention is to provide a
method of electromagnetic interference assessment that facilitates
effective and efficient assessment on the extent of influence caused by
electromagnetic interference.

[0010]Another objective of the present invention is to provide a method of
electromagnetic interference assessment that facilitates cost reduction
of assessment for electromagnetic interference of the receiver.

[0011]The present invention discloses a method of electromagnetic
interference assessment applicable to a receiver. The method comprises
the following steps: initially, scanning a plurality of frequencies;
next, for each scanned frequency, measuring corresponding signal strength
value; finally, based on the correspondence between the frequencies and
the signal strength values, acquiring an analysis curve graph,
furthermore assessing the extent of electromagnetic interference of the
receiver through the acquired analysis curve graph.

[0012]In one embodiment of the present invention, the step of scanning a
plurality of frequencies consists of first setting a frequency reception
range, then sequentially receiving from the lowest frequency of the
frequency reception range to the highest frequency thereof, while the
frequency intended to be received being step-wise increased in order to
measure the corresponding signal strength value.

[0013]In one embodiment of the present invention, the method further
comprises the following steps: providing at least one preferred curve
graph; then comparing the analysis curve graph with the preferred curve
graph; and determining whether or not any electromagnetic interference
occurs in the receiver based on the comparison.

[0014]Through the aforementioned technical solution, the present invention
can be used to record the signal strength value of each reception
frequency, and generates information for determining the reception
performance of the receiver, further facilitating users to precisely and
quickly assess the electromagnetic interference condition of the receiver
with lower cost.

[0015]The aforementioned summary and following detailed descriptions and
appended drawings are all intended to further illustrate the approaches,
means, and effects taken by the present invention to achieve the
prescribed objectives. Other purposes and advantages related to the
present invention will be thoroughly construed in the descriptions and
diagrams set forth infra.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 shows a system architecture schematic diagram for an
embodiment of the receiver according to the present invention;

[0017]FIG. 2 shows a schematic diagram for an embodiment of the assessment
interface according to the present invention;

[0018]FIG. 3 shows a schematic diagram for another embodiment of the
assessment interface according to the present invention;

[0019]FIG. 4 shows a schematic diagram for yet another embodiment of the
assessment interface according to the present invention;

[0020]FIG. 5 shows a diagram for an embodiment of the analysis curve graph
according to the present invention;

[0021]FIG. 6 shows a diagram for another embodiment of the analysis curve
graph according to the present invention; and

[0022]FIG. 7 shows a step-wise flowchart for the method of electromagnetic
interference assessment according to the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0023]The present invention discloses a method of electromagnetic
interference assessment, which, under the circumstances of a receiver not
being connected to a reception antenna, scans the frequencies in the
entire operating frequency range and records the signal strength value of
each frequency, further assessing which frequencies are influenced by
electromagnetic interference based on the acquired signal strength
values, so as to efficiently assess the extent of influence caused by
electromagnetic interference of the receiver, enabling advantages of cost
reduction and time saving as well.

[0024]The major technical characteristic of the present invention are in
that, to automatically scan each frequency in the operating frequency
range of the receiver, and to record the information of signal strength
values thereof for assessing the reception performance in the receiver.
Hereunder only the required hardware architecture and operations thereof
are illustrated; however, those skilled in the art can appreciate that,
in addition to the elements set forth below, other components in the
receiver may also be involved; thus it is by no means to be limited to
what are disclosed herein.

[0025]Initially, refer to FIG. 1, wherein a system architecture schematic
diagram for an embodiment of the receiver according to the present
invention is shown. As illustrated in FIG. 1, the receiver 1 receives
radio frequency (RF) signals indicating the digital media frequency
radiated from a transmitter via an externally connected antenna 2, and
then by using a display unit 3 to render TV programs or audio/video
multimedia. In practical implementations, the receiver 1 can be a digital
TV set, a Set Top Box (STB), or other digital reception system supporting
broadcast standards, and each receiver 1 has its own specific operating
frequency range; i.e. it can only receive digital information transmitted
through each channel located in the operating frequency range. The
receiver 1 comprises at least one tuner 11, an automatic gain control 13,
and a processing unit 15. The tuner 11 may also select specific RF
signals (channel or program), filtering out undesirable RF signals to
prevent possible interference on the intended channel caused by such
undesirable RF signals during frequency reduction process. The automatic
gain control 13 is coupled to the tuner 11, used to perform appropriate
amplification or suppression on the RF signal processed by the tuner 11,
thus assuring normal operations done in the back-end digital processing
unit. The automatic gain control 13 is installed with a register 131 for
storing a signal strength value of the currently received RF signal. The
processing unit 15 is coupled between the automatic gain control 13 and
the display unit 3 for controlling the operations of components in the
receiver 1, so as to transfer the multimedia information generated after
the above-said processes on the RF signals to the display unit 3.

[0026]The method of electromagnetic interference assessment according to
the present invention is to provide an electromagnetic interference
assessment program, which, when executed, enables the display unit 3 to
render the currently received frequency (i.e. the RF signal) and acquires
the signal strength value of the frequency from the register 131 in the
automatic gain control 13. Refer now to FIG. 2, wherein a schematic
diagram for an embodiment of the assessment interface according to the
present invention is shown. As shown in FIG. 2, the display unit 3
generates an assessment interface 21 which shows that the currently
scanned frequency 211 is 4059 MHz, whose signal strength value 213 is
61%, thereby the signal strength or signal quality of the currently
scanned channel may be visualized.

[0027]To identify the extent of electromagnetic interference occurred in
each of the received frequency, the method according to the present
invention is essentially used under a circumstance when the receiver 1
being unplugged/unconnected from the antenna 2. If the antenna 2 is not
connected, then the signal strength of the tested frequency from the
receiver 1 which has good performance and is free from electromagnetic
interference should have a signal strength value to be zero or a rather
small value; however suppose a certain signal strength at some frequency
can still be detected, then it can be determined that the frequency is
subjected to the electromagnetic interference from the motherboard in the
receiver 1. Refer in conjunction to FIGS. 3 and 4, wherein schematic
diagrams for another embodiment of the assessment interface according to
the present invention are shown. As depicted in FIG. 3, after the
execution of electromagnetic interference assessment procedure by a user,
the assessment interface 31 generated by the display unit 3 reveals that
the currently scanned frequency 311 is 3729 MHz, whose signal strength
313 is 0%, thus indicating the extent of electromagnetic interference in
the assessed frequency is comparatively small. Contrarily, as shown in
FIG. 4, the assessment interface 41 shows that the currently received
frequency 411 is 3706 MHz, whose signal strength 413 contains a non-zero
value, thus indicating noise signal may be generated in the assessed
frequency due to layout or wire resistance of the printed circuit board
in the receiver 1, further leading to occurrence of electromagnetic
interference. Through the aforementioned approaches, the user may set a
frequency reception range in the receiver 1; actually, the frequency
reception range can be the operating reception range of the receiver 1,
in which the processing unit 15 of the receiver 1 continuously sends
instructions to the tuner 11 to perform frequency scans, allowing the
tuner 11 to lock on each frequency within the frequency reception range,
further enabling the electromagnetic interference assessment program to
automatically start to sequentially scan from the lowest frequency in the
frequency reception range to the highest frequency with a certain
step-wise frequency increment, thereby scanning through each channel in
the entire frequency reception range and recording the signal strength
value thereof. In this way, the signal strength value at each operating
frequency can be collected in order to generate analysis information
allowing for the tester's references. Refer now to FIGS. 5 and 6, wherein
diagrams of an embodiment for the analysis curve graph according to the
present invention are shown. After completion of frequency scan by the
electromagnetic interference assessment procedure, an analysis curve
graph 5 will be generated based on the correspondence between the
received frequency and the signal strength value thereof. As shown in
FIG. 5, the abscissa on the graph is the frequency, the ordinate
indicates the signal strength value, and small corresponding signal
strength value of each frequency represents good performance in the
receiver 1, which indicates less possibility of occurrence of
electromagnetic interference. Contrarily, the analysis curve graph 6
shown in FIG. 6 reveals greater signal strength values at frequencies
1150 MHz and 1350 MHz, thus indicating occurrence of electromagnetic
interference at such frequencies. Accordingly, the user may perform
necessary modification and adjustment on wiring of the receiver 1 based
on the assessment results, repeat the frequency scan procedure as above,
until an analysis curve graph approximate to what a receiver 1 of good
performance, low extent of electromagnetic interference may demonstrate
is finally acquired.

[0028]In an embodiment of the present invention, other than determining
performance of receiver 1 by manual observation on the analysis curve
graph, it is also possible to store at least one preferred curve graph in
the receiver 1 for reference, in which the processing unit 15 compares
the measured analysis curve graph with the prescribed preferred curve
graph; if the difference between these two curve exceeds a tolerable
range, then the receiver 1 is determined to present occurrence of
electromagnetic interference.

[0029]Finally, refer now to FIG. 7, wherein a step-wise flowchart for the
method of electromagnetic interference assessment according to the
present invention is shown. FIGS. 1 to 6 are also conjunctively referred
for relevant system and process patterns. As depicted in FIG. 7, the said
method of electromagnetic interference assessment comprises the following
steps:

[0030]Initially, a user inputs instructions through a remote control or
enters a specific key combination into the receiver 1 to start the
electromagnetic interference assessment procedure (step S701); the
receiver 1 then scans the channels in the entire frequency reception
range, which begins with the lowest frequency (step S703); subsequently,
the automatic gain control 13 measures the signal strength value at the
currently scanned frequency (step S705); and the processing unit 15
stores the signal strength value recorded in the register 131 and renders
it on the display unit 3 (as shown by the assessment interface 21) (step
S707);

[0031]afterward, the processing unit 15 determines whether or not the
currently scanned frequency is the highest one in the frequency reception
range (step S709); if not, then add the currently received frequency by a
certain fixed increment and receives the updated frequency, continuing
the operation downward from step S705, until all signal strength values
corresponding to the frequencies in the entire frequency reception range
are measured (step S711); if the determination in step S709 is yes, then
it indicates that all frequencies in the frequency reception range have
been scanned through once, and an analysis curve graph is generated based
the correspondence between the frequency and the signal strength value
thereof (step S713), facilitating the user to observe the electromagnetic
interference condition of the receiver 1 at each frequency;

[0032]Finally, the processing unit 15 compares the generated analysis
curve graph with the prescribed preferred curve graph (step S715),
further allowing the user to assess the extent of electromagnetic
interference therein selectively based on the analysis curve graph or the
comparison results (step S717).

[0033]Through the method described supra, the user is able to be aware of
which frequencies are undesirably influenced by electromagnetic
interference to perform adequate amendments, such as correcting wiring on
the printed circuit board or modifying component layout pattern in the
receiver . . . etc., and then after completion of such amendments,
repeats the method provided by the present invention to perform tests on
the receiver, until the test results are qualified.

[0034]In accordance with the aforementioned detailed descriptions of
embodiments, it can be seen that the method of electromagnetic
interference assessment of the present invention scans entire frequency
reception range of the receiver, and records signal strength value of
each received frequency, further assessing which frequencies are
influenced by electromagnetic interference based on the correspondence
between frequency and signal strength value. Thereby, it is convenient to
observe the electromagnetic interference condition of the receiver, and
to appreciate the Electro Magnetic Compatibility (EMC) of the receiver
from the extent of electromagnetic interference, accordingly providing
improvements on the drawbacks of expensive cost and operation time
required for conventional receiver tests.

[0035]The aforementioned disclosure simply sets forth the detailed
descriptions and appended drawings for the embodiments of the present
invention, rather than being used to limit the present invention. The
scope of the present invention should be based on the following claims;
all changes and modifications that those skilled in the art may
conveniently consider in the fields of the present invention are
reasonably deemed to be encompassed within the scope of the present
invention delineated by the claims disclosed hereunder.